<script lang="ts">
	import Fuse from 'fuse.js';
	import { toast } from 'svelte-sonner';
	import { v4 as uuidv4 } from 'uuid';
	import { PaneGroup, Pane, PaneResizer } from 'paneforge';

	import { onMount, getContext, onDestroy, tick } from 'svelte';
	const i18n = getContext('i18n');

	import { goto } from '$app/navigation';
	import { page } from '$app/stores';
	import { mobile, showSidebar, knowledge as _knowledge } from '$lib/stores';

	import { updateFileDataContentById, uploadFile } from '$lib/apis/files';
	import {
		addFileToKnowledgeById,
		getKnowledgeById,
		getKnowledgeItems,
		removeFileFromKnowledgeById,
		resetKnowledgeById,
		updateFileFromKnowledgeById,
		updateKnowledgeById
	} from '$lib/apis/knowledge';

	import { transcribeAudio } from '$lib/apis/audio';
	import { blobToFile } from '$lib/utils';
	import { processFile } from '$lib/apis/retrieval';

	import Spinner from '$lib/components/common/Spinner.svelte';
	import Files from './Collection/Files.svelte';
	import AddFilesPlaceholder from '$lib/components/AddFilesPlaceholder.svelte';

	import AddContentMenu from './Collection/AddContentMenu.svelte';
	import AddTextContentModal from './Collection/AddTextContentModal.svelte';

	import SyncConfirmDialog from '../../common/ConfirmDialog.svelte';
	import RichTextInput from '$lib/components/common/RichTextInput.svelte';
	import EllipsisVertical from '$lib/components/icons/EllipsisVertical.svelte';
	import Drawer from '$lib/components/common/Drawer.svelte';
	import ChevronLeft from '$lib/components/icons/ChevronLeft.svelte';
	import MenuLines from '$lib/components/icons/MenuLines.svelte';

	let largeScreen = true;

	let pane;
	let showSidepanel = true;
	let minSize = 0;

	type Knowledge = {
		id: string;
		name: string;
		description: string;
		data: {
			file_ids: string[];
		};
		files: any[];
	};

	let id = null;
	let knowledge: Knowledge | null = null;
	let query = '';

	let showAddTextContentModal = false;
	let showSyncConfirmModal = false;

	let inputFiles = null;

	let filteredItems = [];
	$: if (knowledge) {
		fuse = new Fuse(knowledge.files, {
			keys: ['meta.name', 'meta.description']
		});
	}

	$: if (fuse) {
		filteredItems = query
			? fuse.search(query).map((e) => {
					return e.item;
				})
			: (knowledge?.files ?? []);
	}

	let selectedFile = null;
	let selectedFileId = null;

	$: if (selectedFileId) {
		const file = (knowledge?.files ?? []).find((file) => file.id === selectedFileId);
		if (file) {
			file.data = file.data ?? { content: '' };
			selectedFile = file;
		} else {
			selectedFile = null;
		}
	} else {
		selectedFile = null;
	}

	let fuse = null;
	let debounceTimeout = null;
	let mediaQuery;
	let dragged = false;

	const createFileFromText = (name, content) => {
		const blob = new Blob([content], { type: 'text/plain' });
		const file = blobToFile(blob, `${name}.txt`);

		console.log(file);
		return file;
	};

	const uploadFileHandler = async (file) => {
		console.log(file);

		const tempItemId = uuidv4();
		const fileItem = {
			type: 'file',
			file: '',
			id: null,
			url: '',
			name: file.name,
			size: file.size,
			status: 'uploading',
			error: '',
			itemId: tempItemId
		};

		if (fileItem.size == 0) {
			toast.error($i18n.t('You cannot upload an empty file.'));
			return null;
		}

		knowledge.files = [...(knowledge.files ?? []), fileItem];

		// Check if the file is an audio file and transcribe/convert it to text file
		if (['audio/mpeg', 'audio/wav', 'audio/ogg', 'audio/x-m4a'].includes(file['type'])) {
			const res = await transcribeAudio(localStorage.token, file).catch((error) => {
				toast.error(error);
				return null;
			});

			if (res) {
				console.log(res);
				const blob = new Blob([res.text], { type: 'text/plain' });
				file = blobToFile(blob, `${file.name}.txt`);
			}
		}

		try {
			const uploadedFile = await uploadFile(localStorage.token, file).catch((e) => {
				toast.error(e);
				return null;
			});

			if (uploadedFile) {
				console.log(uploadedFile);
				knowledge.files = knowledge.files.map((item) => {
					if (item.itemId === tempItemId) {
						item.id = uploadedFile.id;
					}

					// Remove temporary item id
					delete item.itemId;
					return item;
				});
				await addFileHandler(uploadedFile.id);
			} else {
				toast.error($i18n.t('Failed to upload file.'));
			}
		} catch (e) {
			toast.error(e);
		}
	};

	const uploadDirectoryHandler = async () => {
		// Check if File System Access API is supported
		const isFileSystemAccessSupported = 'showDirectoryPicker' in window;

		try {
			if (isFileSystemAccessSupported) {
				// Modern browsers (Chrome, Edge) implementation
				await handleModernBrowserUpload();
			} else {
				// Firefox fallback
				await handleFirefoxUpload();
			}
		} catch (error) {
			handleUploadError(error);
		}
	};

	// Helper function to check if a path contains hidden folders
	const hasHiddenFolder = (path) => {
		return path.split('/').some((part) => part.startsWith('.'));
	};

	// Modern browsers implementation using File System Access API
	const handleModernBrowserUpload = async () => {
		const dirHandle = await window.showDirectoryPicker();
		let totalFiles = 0;
		let uploadedFiles = 0;

		// Function to update the UI with the progress
		const updateProgress = () => {
			const percentage = (uploadedFiles / totalFiles) * 100;
			toast.info(`Upload Progress: ${uploadedFiles}/${totalFiles} (${percentage.toFixed(2)}%)`);
		};

		// Recursive function to count all files excluding hidden ones
		async function countFiles(dirHandle) {
			for await (const entry of dirHandle.values()) {
				// Skip hidden files and directories
				if (entry.name.startsWith('.')) continue;

				if (entry.kind === 'file') {
					totalFiles++;
				} else if (entry.kind === 'directory') {
					// Only process non-hidden directories
					if (!entry.name.startsWith('.')) {
						await countFiles(entry);
					}
				}
			}
		}

		// Recursive function to process directories excluding hidden files and folders
		async function processDirectory(dirHandle, path = '') {
			for await (const entry of dirHandle.values()) {
				// Skip hidden files and directories
				if (entry.name.startsWith('.')) continue;

				const entryPath = path ? `${path}/${entry.name}` : entry.name;

				// Skip if the path contains any hidden folders
				if (hasHiddenFolder(entryPath)) continue;

				if (entry.kind === 'file') {
					const file = await entry.getFile();
					const fileWithPath = new File([file], entryPath, { type: file.type });

					await uploadFileHandler(fileWithPath);
					uploadedFiles++;
					updateProgress();
				} else if (entry.kind === 'directory') {
					// Only process non-hidden directories
					if (!entry.name.startsWith('.')) {
						await processDirectory(entry, entryPath);
					}
				}
			}
		}

		await countFiles(dirHandle);
		updateProgress();

		if (totalFiles > 0) {
			await processDirectory(dirHandle);
		} else {
			console.log('No files to upload.');
		}
	};

	// Firefox fallback implementation using traditional file input
	const handleFirefoxUpload = async () => {
		return new Promise((resolve, reject) => {
			// Create hidden file input
			const input = document.createElement('input');
			input.type = 'file';
			input.webkitdirectory = true;
			input.directory = true;
			input.multiple = true;
			input.style.display = 'none';

			// Add input to DOM temporarily
			document.body.appendChild(input);

			input.onchange = async () => {
				try {
					const files = Array.from(input.files)
						// Filter out files from hidden folders
						.filter((file) => !hasHiddenFolder(file.webkitRelativePath));

					let totalFiles = files.length;
					let uploadedFiles = 0;

					// Function to update the UI with the progress
					const updateProgress = () => {
						const percentage = (uploadedFiles / totalFiles) * 100;
						toast.info(
							`Upload Progress: ${uploadedFiles}/${totalFiles} (${percentage.toFixed(2)}%)`
						);
					};

					updateProgress();

					// Process all files
					for (const file of files) {
						// Skip hidden files (additional check)
						if (!file.name.startsWith('.')) {
							const relativePath = file.webkitRelativePath || file.name;
							const fileWithPath = new File([file], relativePath, { type: file.type });

							await uploadFileHandler(fileWithPath);
							uploadedFiles++;
							updateProgress();
						}
					}

					// Clean up
					document.body.removeChild(input);
					resolve();
				} catch (error) {
					reject(error);
				}
			};

			input.onerror = (error) => {
				document.body.removeChild(input);
				reject(error);
			};

			// Trigger file picker
			input.click();
		});
	};

	// Error handler
	const handleUploadError = (error) => {
		if (error.name === 'AbortError') {
			toast.info('Directory selection was cancelled');
		} else {
			toast.error('Error accessing directory');
			console.error('Directory access error:', error);
		}
	};

	// Helper function to maintain file paths within zip
	const syncDirectoryHandler = async () => {
		if ((knowledge?.files ?? []).length > 0) {
			const res = await resetKnowledgeById(localStorage.token, id).catch((e) => {
				toast.error(e);
			});

			if (res) {
				knowledge = res;
				toast.success($i18n.t('Knowledge reset successfully.'));

				// Upload directory
				uploadDirectoryHandler();
			}
		} else {
			uploadDirectoryHandler();
		}
	};

	const addFileHandler = async (fileId) => {
		const updatedKnowledge = await addFileToKnowledgeById(localStorage.token, id, fileId).catch(
			(e) => {
				toast.error(e);
				return null;
			}
		);

		if (updatedKnowledge) {
			knowledge = updatedKnowledge;
			toast.success($i18n.t('File added successfully.'));
		} else {
			toast.error($i18n.t('Failed to add file.'));
			knowledge.files = knowledge.files.filter((file) => file.id !== fileId);
		}
	};

	const deleteFileHandler = async (fileId) => {
		const updatedKnowledge = await removeFileFromKnowledgeById(
			localStorage.token,
			id,
			fileId
		).catch((e) => {
			toast.error(e);
		});

		if (updatedKnowledge) {
			knowledge = updatedKnowledge;
			toast.success($i18n.t('File removed successfully.'));
		}
	};

	const updateFileContentHandler = async () => {
		const fileId = selectedFile.id;
		const content = selectedFile.data.content;

		const res = updateFileDataContentById(localStorage.token, fileId, content).catch((e) => {
			toast.error(e);
		});

		const updatedKnowledge = await updateFileFromKnowledgeById(
			localStorage.token,
			id,
			fileId
		).catch((e) => {
			toast.error(e);
		});

		if (res && updatedKnowledge) {
			knowledge = updatedKnowledge;
			toast.success($i18n.t('File content updated successfully.'));
		}
	};

	const changeDebounceHandler = () => {
		console.log('debounce');
		if (debounceTimeout) {
			clearTimeout(debounceTimeout);
		}

		debounceTimeout = setTimeout(async () => {
			if (knowledge.name.trim() === '' || knowledge.description.trim() === '') {
				toast.error($i18n.t('Please fill in all fields.'));
				return;
			}

			const res = await updateKnowledgeById(localStorage.token, id, {
				name: knowledge.name,
				description: knowledge.description
			}).catch((e) => {
				toast.error(e);
			});

			if (res) {
				toast.success($i18n.t('Knowledge updated successfully'));
				_knowledge.set(await getKnowledgeItems(localStorage.token));
			}
		}, 1000);
	};

	const handleMediaQuery = async (e) => {
		if (e.matches) {
			largeScreen = true;
		} else {
			largeScreen = false;
		}
	};

	const onDragOver = (e) => {
		e.preventDefault();
		dragged = true;
	};

	const onDragLeave = () => {
		dragged = false;
	};

	const onDrop = async (e) => {
		e.preventDefault();
		dragged = false;

		if (e.dataTransfer?.files) {
			const inputFiles = e.dataTransfer?.files;

			if (inputFiles && inputFiles.length > 0) {
				for (const file of inputFiles) {
					await uploadFileHandler(file);
				}
			} else {
				toast.error($i18n.t(`File not found.`));
			}
		}
	};

	onMount(async () => {
		// listen to resize 1024px
		mediaQuery = window.matchMedia('(min-width: 1024px)');

		mediaQuery.addEventListener('change', handleMediaQuery);
		handleMediaQuery(mediaQuery);

		// Select the container element you want to observe
		const container = document.getElementById('collection-container');

		// initialize the minSize based on the container width
		minSize = !largeScreen ? 100 : Math.floor((300 / container.clientWidth) * 100);

		// Create a new ResizeObserver instance
		const resizeObserver = new ResizeObserver((entries) => {
			for (let entry of entries) {
				const width = entry.contentRect.width;
				// calculate the percentage of 300
				const percentage = (300 / width) * 100;
				// set the minSize to the percentage, must be an integer
				minSize = !largeScreen ? 100 : Math.floor(percentage);

				if (showSidepanel) {
					if (pane && pane.isExpanded() && pane.getSize() < minSize) {
						pane.resize(minSize);
					}
				}
			}
		});

		// Start observing the container's size changes
		resizeObserver.observe(container);

		if (pane) {
			pane.expand();
		}

		id = $page.params.id;

		const res = await getKnowledgeById(localStorage.token, id).catch((e) => {
			toast.error(e);
			return null;
		});

		if (res) {
			knowledge = res;
		} else {
			goto('/workspace/knowledge');
		}

		const dropZone = document.querySelector('body');
		dropZone?.addEventListener('dragover', onDragOver);
		dropZone?.addEventListener('drop', onDrop);
		dropZone?.addEventListener('dragleave', onDragLeave);
	});

	onDestroy(() => {
		mediaQuery?.removeEventListener('change', handleMediaQuery);
		const dropZone = document.querySelector('body');
		dropZone?.removeEventListener('dragover', onDragOver);
		dropZone?.removeEventListener('drop', onDrop);
		dropZone?.removeEventListener('dragleave', onDragLeave);
	});
</script>

{#if dragged}
	<div
		class="fixed {$showSidebar
			? 'left-0 md:left-[260px] md:w-[calc(100%-260px)]'
			: 'left-0'}  w-full h-full flex z-50 touch-none pointer-events-none"
		id="dropzone"
		role="region"
		aria-label="Drag and Drop Container"
	>
		<div class="absolute w-full h-full backdrop-blur bg-gray-800/40 flex justify-center">
			<div class="m-auto pt-64 flex flex-col justify-center">
				<div class="max-w-md">
					<AddFilesPlaceholder>
						<div class=" mt-2 text-center text-sm dark:text-gray-200 w-full">
							Drop any files here to add to my documents
						</div>
					</AddFilesPlaceholder>
				</div>
			</div>
		</div>
	</div>
{/if}

<SyncConfirmDialog
	bind:show={showSyncConfirmModal}
	message={$i18n.t(
		'This will reset the knowledge base and sync all files. Do you wish to continue?'
	)}
	on:confirm={() => {
		syncDirectoryHandler();
	}}
/>

<AddTextContentModal
	bind:show={showAddTextContentModal}
	on:submit={(e) => {
		const file = createFileFromText(e.detail.name, e.detail.content);
		uploadFileHandler(file);
	}}
/>

<input
	id="files-input"
	bind:files={inputFiles}
	type="file"
	multiple
	hidden
	on:change={async () => {
		if (inputFiles && inputFiles.length > 0) {
			for (const file of inputFiles) {
				await uploadFileHandler(file);
			}

			inputFiles = null;
			const fileInputElement = document.getElementById('files-input');

			if (fileInputElement) {
				fileInputElement.value = '';
			}
		} else {
			toast.error($i18n.t(`File not found.`));
		}
	}}
/>

<div class="flex flex-col w-full h-full max-h-[100dvh]" id="collection-container">
	{#if id && knowledge}
		<div class="flex flex-row flex-1 h-full max-h-full pb-2.5">
			<PaneGroup direction="horizontal">
				<Pane
					bind:pane
					defaultSize={minSize}
					collapsible={true}
					maxSize={50}
					{minSize}
					class="h-full"
					onExpand={() => {
						showSidepanel = true;
					}}
					onCollapse={() => {
						showSidepanel = false;
					}}
				>
					<div
						class="{largeScreen ? 'flex-shrink-0' : 'flex-1'}
						flex
						py-2
						rounded-2xl
						border
						border-gray-50
						h-full
						dark:border-gray-850"
					>
						<div class=" flex flex-col w-full space-x-2 rounded-lg h-full">
							<div class="w-full h-full flex flex-col">
								<div class=" px-3">
									<div class="flex py-1">
										<div class=" self-center ml-1 mr-3">
											<svg
												xmlns="http://www.w3.org/2000/svg"
												viewBox="0 0 20 20"
												fill="currentColor"
												class="w-4 h-4"
											>
												<path
													fill-rule="evenodd"
													d="M9 3.5a5.5 5.5 0 100 11 5.5 5.5 0 000-11zM2 9a7 7 0 1112.452 4.391l3.328 3.329a.75.75 0 11-1.06 1.06l-3.329-3.328A7 7 0 012 9z"
													clip-rule="evenodd"
												/>
											</svg>
										</div>
										<input
											class=" w-full text-sm pr-4 py-1 rounded-r-xl outline-none bg-transparent"
											bind:value={query}
											placeholder={$i18n.t('Search Collection')}
											on:focus={() => {
												selectedFileId = null;
											}}
										/>

										<div>
											<AddContentMenu
												on:upload={(e) => {
													if (e.detail.type === 'directory') {
														uploadDirectoryHandler();
													} else if (e.detail.type === 'text') {
														showAddTextContentModal = true;
													} else {
														document.getElementById('files-input').click();
													}
												}}
												on:sync={(e) => {
													showSyncConfirmModal = true;
												}}
											/>
										</div>
									</div>
								</div>

								{#if filteredItems.length > 0}
									<div class=" flex overflow-y-auto h-full w-full scrollbar-hidden text-xs">
										<Files
											files={filteredItems}
											{selectedFileId}
											on:click={(e) => {
												selectedFileId = selectedFileId === e.detail ? null : e.detail;
											}}
											on:delete={(e) => {
												console.log(e.detail);

												selectedFileId = null;
												deleteFileHandler(e.detail);
											}}
										/>
									</div>
								{:else}
									<div class="m-auto text-gray-500 text-xs">{$i18n.t('No content found')}</div>
								{/if}
							</div>
						</div>
					</div>
				</Pane>

				{#if largeScreen}
					<PaneResizer class="relative flex w-2 items-center justify-center bg-background group">
						<div class="z-10 flex h-7 w-5 items-center justify-center rounded-sm">
							<EllipsisVertical className="size-4 invisible group-hover:visible" />
						</div>
					</PaneResizer>
					<Pane>
						<div class="flex-1 flex justify-start h-full max-h-full">
							{#if selectedFile}
								<div class=" flex flex-col w-full h-full max-h-full ml-2.5">
									<div class="flex-shrink-0 mb-2 flex items-center">
										{#if !showSidepanel}
											<div class="-translate-x-2">
												<button
													class="w-full text-left text-sm p-1.5 rounded-lg dark:text-gray-300 dark:hover:text-white hover:bg-black/5 dark:hover:bg-gray-850"
													on:click={() => {
														pane.expand();
													}}
												>
													<ChevronLeft strokeWidth="2.5" />
												</button>
											</div>
										{/if}

										<div class=" flex-1 text-2xl font-medium">
											<a
												class="hover:text-gray-500 hover:dark:text-gray-100 hover:underline flex-grow line-clamp-1"
												href={selectedFile.id ? `/api/v1/files/${selectedFile.id}/content` : '#'}
												target="_blank"
											>
												{selectedFile?.meta?.name}
											</a>
										</div>

										<div>
											<button
												class="self-center w-fit text-sm py-1 px-2.5 dark:text-gray-300 dark:hover:text-white hover:bg-black/5 dark:hover:bg-white/5 rounded-lg"
												on:click={() => {
													updateFileContentHandler();
												}}
											>
												{$i18n.t('Save')}
											</button>
										</div>
									</div>

									<div
										class=" flex-1 w-full h-full max-h-full text-sm bg-transparent outline-none overflow-y-auto scrollbar-hidden"
									>
										{#key selectedFile.id}
											<RichTextInput
												className="input-prose-sm"
												bind:value={selectedFile.data.content}
												placeholder={$i18n.t('Add content here')}
											/>
										{/key}
									</div>
								</div>
							{:else}
								<div class="m-auto pb-32">
									<div>
										<div class=" flex w-full mt-1 mb-3.5">
											<div class="flex-1">
												<div class="flex items-center justify-between w-full px-0.5 mb-1">
													<div class="w-full">
														<input
															type="text"
															class="text-center w-full font-medium text-3xl font-primary bg-transparent outline-none"
															bind:value={knowledge.name}
															on:input={() => {
																changeDebounceHandler();
															}}
														/>
													</div>
												</div>

												<div class="flex w-full px-1">
													<input
														type="text"
														class="text-center w-full text-gray-500 bg-transparent outline-none"
														bind:value={knowledge.description}
														on:input={() => {
															changeDebounceHandler();
														}}
													/>
												</div>
											</div>
										</div>
									</div>

									<div class=" mt-2 text-center text-sm text-gray-200 dark:text-gray-700 w-full">
										{$i18n.t('Select a file to view or drag and drop a file to upload')}
									</div>
								</div>
							{/if}
						</div>
					</Pane>
				{:else if !largeScreen && selectedFileId !== null}
					<Drawer
						className="h-full"
						show={selectedFileId !== null}
						on:close={() => {
							selectedFileId = null;
						}}
					>
						<div class="flex flex-col justify-start h-full max-h-full p-2">
							<div class=" flex flex-col w-full h-full max-h-full">
								<div class="flex-shrink-0 mt-1 mb-2 flex items-center">
									<div class="mr-2">
										<button
											class="w-full text-left text-sm p-1.5 rounded-lg dark:text-gray-300 dark:hover:text-white hover:bg-black/5 dark:hover:bg-gray-850"
											on:click={() => {
												selectedFileId = null;
											}}
										>
											<ChevronLeft strokeWidth="2.5" />
										</button>
									</div>
									<div class=" flex-1 text-xl line-clamp-1">
										{selectedFile?.meta?.name}
									</div>

									<div>
										<button
											class="self-center w-fit text-sm py-1 px-2.5 dark:text-gray-300 dark:hover:text-white hover:bg-black/5 dark:hover:bg-white/5 rounded-lg"
											on:click={() => {
												updateFileContentHandler();
											}}
										>
											{$i18n.t('Save')}
										</button>
									</div>
								</div>

								<div
									class=" flex-1 w-full h-full max-h-full py-2.5 px-3.5 rounded-lg text-sm bg-transparent overflow-y-auto scrollbar-hidden"
								>
									{#key selectedFile.id}
										<RichTextInput
											className="input-prose-sm"
											bind:value={selectedFile.data.content}
											placeholder={$i18n.t('Add content here')}
										/>
									{/key}
								</div>
							</div>
						</div>
					</Drawer>
				{/if}
			</PaneGroup>
		</div>
	{:else}
		<Spinner />
	{/if}
</div>
